British Transport Police is appealing for information after a member of station staff was assaulted on board a train at Southend Victoria station.
Investigators have released CCTV of a man they would like to speak to in connection with the incident, which took place on Monday, 25 March.
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Radical new trains that will carry millions of passengers on the Thameslink network will be launched today.
Tuesday morning's forecast for the east of the region
Tuesday morning's forecast for the west of the region